DIET DURING PREGNANCY
A woman's nutrition at this time must cover not only her needs and requirements but also those of the future baby. The need for proteins, vitamins and minerals increases. The weight that the mother gains provides a parameter with which to evaluate maternal-foetal health.During pregnancy and breast-feeding the nutritional needs are greater in order to permit the growth and development of the foetus and thereafter the newborn. These changes require a specific diet.
Energetic
requirements
The energy requirements of the pregnant woman depend on her
constitution, nutritional state, whether or not she is at her ideal
weight, and how regularly she does physical exercise.Women who prior to pregnancy were below their ideal weight should increase their calorific intake by 300-400 kcal/day. Those whose weight was ideal should supplement their diet with 200 kcal/day. Finally, women who prior to the pregnancy were above their ideal weight, should do so with 100 kcal/day.
Protein requirements
During pregnancy the required intake of proteins is higher in order to cover the requirements for the growth of the foetus, the placenta and the maternal tissues.It is estimated that the proteins deposited within these tissues is as much as 925 gr. Some 70% of proteins from the diet come to form part of the maternal tissues.
This is why a pregnant woman requires an additional intake of 10 gr. of proteins/day. An intake of 70 gr. of proteins each day is more than enough to satisfy overall protein requirements.
Essential fatty acid requirements
The supply of essential fatty acids in the diet in sufficient quantities is fundamental for the development of the placenta and the foetus.A minimal supply of 3% of energy as linoleic acid and 0,5% as alpha-linolenic ensures the adequate development of the maternal tissues and the foetus during pregnancy.
In addition, other fatty acids (such as arachidonic and docosahexaenoic) are fundamental to the development of the vessels of the placenta, in turn essential for the foetus to reach an adequate weight.
Mineral requirements
Calcium. The metabolism of calcium is altered profoundly during pregnancy due to hormonal changes, which produce an increase in the absorption and retention of the mineral, and due to the high concentrations in the blood of a component of vitamin D.The foetus accumulates 330 gr. of calcium during its formation, therefore the calcium of the mother diminishes by some 5%, which is quickly recovered after the birth.
The recommended intake of calcium for pregnant women is 1200 mg/day, which represents an increase of 400 mg. on the normal intake of a woman over the age of 25.
A low calcium intake during pregnancy leads to a reduction in the deposits of this mineral in the mother and can increase the risk of osteoporosis in later years.
Magnesium. The adult organsim contains some 350 mg. of magnesium per kg. of body weight. 60% is in the skeleton, 20% in the skeletal muscle and 20% in other tissues.
Young women who subject themselves to weight loss diets without medical supervision have deficits of magnesium, which can lead to hypertension and a greater risk of high blood pressure (pre-eclampsia) in pregnant women. For this reason, it is advisable that during pregnancy, there is a minimum magnesium intake of 320 mg/day.
Iron. Women have a greater iron requirement than men due to its periodic loss during menstruation. These losses can be increased when using intrauterine devices such as contraceptives.
The case of pregnant women represents a special circumstance as they need iron not only for their own organism, but also to cover the needs of the foetus and the placenta. This is why iron supplements or foods enriched with iron are often taken during pregnancy.
To prevent iron deficiency during pregnancy the systematic daily administration of iron is recommended (preferably in ferrous form), beginning from the 12th week of pregnancy, as well as a balanced diet that contains factors which favour the absorption of iron, such as vitamin C and meat.
However, excessive iron supplementation should be avoided as it can provoke intestinal problems and interfere with the absorption of other mineral elements such as zinc and copper which are also essential to foetal development.
If enriched foods are used, these must contain iron in elevated bioavailability form and should not be taken with liquids that can interfere with absorption, such as coffee or tea.
Zinc. Zinc in the blood begins to diminish at the start of pregnancy and continues to do so until birth, reaching a concentration some 35% below that of non-pregnant women.
The daily recommended intake of zinc during pregnancy is 15 mg/day, which represents 3 mg. more than normal, in order to compensate for foetal requirements.
The usual intake for pregnant women tends to be less (between 9 and 11 mg/day), and in vegetarian women much less, which is why an increase in the diet is recommended, up to 15 mg.
Copper. In laboratory animals, maternal copper deficiency causes infertility, miscarriage and foetal death. However, this has not been proven in humans. For this reason, an intake of copper above the normal adult amount is not recommended. However, when zinc supplements are taken, a daily supplement of 2 mg. of copper is recommended because copper is absorbed to a lesser degree when zinc is administered.
Iodine. Iodine deficiency during pregnancy causes a disease (foetal hypothyroidism) which has a number of profound consequences such as cretinism (mental retardation), miscarriage, foetal anomalies, profound deafness and foetal death.
Iodine is an essential part of the thyroid hormones, which are necessary for the normal development of the brain and its maturation. The recommended intake for pregnant women is 175 micrograms/day.
Need for vitamins
Vitamin D. Vitmain D is actively transported from the placenta to the foetus. Vitamin D deficiency during pregnancy is associated with various alterations in the metabolism of calcium in both the mother and the foetus, such as a reduction of calcium in the blood (neonatal hypocalcemia) and tetany, infant hypoplasia of dental enamel and maternal osteomalacia.A supplement of 10 micrograms/day in women affected reduces the incidence of neonatal hypocalcemia. Higher doses (25 micrograms) increase weight gain and stature in postnatal children.
Vitamin B6.Pregnant women have lower concentrations of vitamin B6 than non-pregnant women. On the other hand, the foetus maintains very high levels. More than 10 mg/day are needed to prevent a reduction in the mother.
It is also advisable to take 0,6 mg. of vitamin B6 up to an intake of 2,2 mg/day, as higher intakes do not correlate with specific benefits for the mother or foetus.
Vitamin C. Women who have taken oral contraceptives for long periods of time, those who consume salicylates (Aspirin), smokers and those who consume alcohol and drugs, as well as women who have had several children, require more vitamin C, and should therefore receive a supplement of 50 mg/day and should increase their consumption of fruit and vegetables.
In any event, the pregnant woman requires 70 mg/day more than non-pregnant women.
Folic Acid. Folic acid deficiency occurs for various reasons, such as inadequate dietary habits, restrictive diets for weight control and slimming, the consumption and abuse of alcohol and tabacco.
The supplement required to maintain normal levels of folate in the red blood cells (eritrocytes) of almost all pregnant women is a minimum of 100 micrograms/day, but it is recommended that to cover all requirements the daily supplement should be in the order of 200-300 micrograms daily.
Mothers, while breast-feeding their babies, need more folate. The folate content of maternal milk is 50-60 micrograms/litre (m/L), so assuming a daily production of 700 m/L of milk, an additional average intake of 100 micrograms/day is recommended. more information: www.pulevasalud.com